


Tentillum

by TRASHCAKE



Category: NCT (Band)
Genre: Alternate Universe - College/University, Alternate Universe - Future, Alternate Universe - Space, Double Penetration, Established Relationship, I Wrote This Instead of Sleeping, M/M, Plot What Plot/Porn Without Plot, Rimming, Smut, Tentacle Sex, Tentacles, The Author Regrets Nothing, The Author is also drunk
Language: English
Status: Completed
Published: 2019-04-29
Updated: 2019-04-29
Packaged: 2020-02-09 18:34:22
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,289
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18643765
Author URL: https://archiveofourown.org/users/TRASHCAKE/pseuds/TRASHCAKE
Summary: Yuta loves Sicheng and all of his surprises.





	Tentillum

**Author's Note:**

  * For [bias_wrecked](https://archiveofourown.org/users/bias_wrecked/gifts).



> Mara: hey so yuwintacles  
> Me: say no more
> 
> My smut skills are so rusty, please forgive me.

Yuta has been interested in Sicheng since the moment their eyes first made contact. Across the room, Intergalactic Relations, 10am Pluto Standard Time. He’s cute with his pastel pink skin and even pinker hair, Yuta’s exchange student ass can’t resist the charms of adorable alien boys. 

The University of Pluto is a conglomeration of all known species, coming together to learn about each other and the universe that they inhabit. A multicultural facility with a focus on exemplary education. Or so the pamphlet says. 

Everyone who’s ever heard of UoP knows it’s a hub of interspecies sexual experimentation and it’s half the reason Yuta applied in the first place. He’s a human, but his interests lie in those outside of his race, hot aliens and their various alien appendages warming his bed more often than not. 

He’s a little bit free with his love, so what. He’s more than capable of commitment, and it’s something he’s set his eye on since the moment he met Sicheng. He’s Martian, one of the many races born on the red planet. They don’t need water to live, which _fascinates_ Yuta, who pays a pretty penny for the Earthian imported stuff. 

Sicheng is cute, Sicheng is feisty, Sicheng is as hot as the planet he was born on. He resists Yuta’s charms until the bitter end, giving in and kissing him hard on the lips during one of their many study dates. 

It’s the best kiss of Yuta’s life, one where he’s dazed and happy by the end of it, walking out of the library with a blushing SIcheng’s hand in his. He’d call them an ‘It’ couple, but this is university, not high school. No one knows who anyone else is, outside their classes or degree. 

They’re still somewhat of an anomaly, though. Interspecies couples aren’t common, despite all the copulation happening on campus. Most people that attend UoP tend to be in it for the experimentation, preferring to go home and date within their own gene pool. 

Not Yuta, though. He’s in love. He’s already applying for jobs on Mars come graduation, the need for humans in the workforce high but the willingness low, due to the terrible weather and the recent addition of Earth to the Planetary Alliance. 

He’s assured a job on Sicheng’s home planet, an apartment with his boyfriend and a career he’s actually interested in. All he’s gotta do is graduate. 

Being with Sicheng is the dream, he keeps Yuta grounded and showers him with affection when he needs it. He’s smart, he’s capable, he’s Yuta’s dream boyfriend and he feels like the luckiest human in the known galaxy with each moment they spend together. 

Of course, Yuta has _needs_ and Sicheng is more than happy to fill them. They haven’t had sex, because Sicheng hasn’t, yet, and is waiting for something more than a quick fuck when their roommates aren’t home, says he wants it to be special, has something to show Yuta. 

Yuta is more than excited, but completely happy with Sicheng’s mouth and hands, more than willing to return the favour more often than not. Sicheng looks so pretty in the throes of pleasure, and Yuta honestly can’t wait to wreck him. 

He’s been asked, multiple times, not to look up Martian biology, just for the surprise of it all. Yuta is nothing but obedient, straying from pages on Martian sex organs because he’s already intimately acquainted with Sicheng’s. 

But there’s something missing, something he doesn’t quite know. A secret that’s being kept from him, for the strangest of reasons. 

It’s not an issue, because Yuta loves Sicheng. 

He just can’t _wait_ to find out. 

\------

It happens sooner rather than later. 

He’s talking to Jaehyun, one of the other humans on campus, who mentions his night with an unnamed Martian who, quote, fucked him so hard he couldn’t walk the next day. 

“I thought it was a myth,” he admits, “both the tentacles and the not being able to walk thing.” 

“Wait,” Yuta says, putting a hand up to stop Jaehyun’s rambling. “Tentacles?” 

“You’re dating a Martian, you should know,” Jaehyun shrugs, goes back to his comm device, most likely messaging the Martian from a few nights before. “They’ve got tentacles on their back, and they’re _wonderful_.” 

“I’ve never seen Sicheng’s tentacles,” he admits, explains their sex life in the most neutral way possible. “He hasn’t shown me, yet.” 

“That’s a shame,” Jaehyun sighs dreamily, brightens as his message receives a response. “They’re a lot of fun.” 

“What’s the name of this Martian you’re messaging, anyway?” 

Jaehyun yelps, caught, he hurries to shove his comm device into his pocket. 

“Johnny,” he admits, speaking of one of Sicheng’s friends. It’s funny how out of everyone on campus, Jaehyun is enamoured with the one dude that Sicheng grew up with. 

“He’s a good guy.” 

Johnny’s a little more magenta than Sicheng, a different race within the species. Like Jaehyun is Korean while Yuta is Japanese, each species has its subset of different races. They speak the same common tongue while on campus, the Intergalactic Dialect that combines so many different languages into one. 

“That he is,” Jaehyun sighs dreamily. 

It’s disgusting, honestly, but Yuta now understands how other people feel when he talks about Sicheng. It’s _love_ , and he’s happy for his friend. 

“How come Sicheng hasn’t gotten the boys out for you?” he continues, “they’re like, the most sensitive part of a Martian.” 

“No idea,” Yuta responds, thinks about messaging his boyfriend, thinks against it the next second. “But it’s probably a conversation we need to have.” 

“Humans are known sluts, though? We’re into everything alien. So it’s not like he’s afraid of what you think of them?” 

Yuta and Jaehyun are living proof of the stereotype, having met during a mutual walk of shame from the bedroom of two housemates. Grabbing breakfast and discussing their conquests, it’s a friendship formed on the back of debauchery. 

“You never know,” Yuta hums, “I don’t think he knew about my _reputation_ before we started dating.” 

And it’s not like Yuta hasn’t been around tentacles before, there are multiple races on campus who possess them and he’s well acquainted with the appendages. He always jokes about being a bit promiscuous, but his unrelenting devotion to Sicheng prior to their relationship may have ruined the truth behind them. 

Either way, they have some talking to do, maybe some kissing, maybe something more. 

Because if there’s one thing Yuta loves, it’s tentacles. 

The fact that they’re attached to his boyfriend is just a bonus. 

\------

His mouth around Sicheng’s cock, whose back arches off the bed in pleasure. Yuta still intends to talk to him, but he’s been jumped, a needy boyfriend attached to his lips since the moment he returned to his room. 

And Yuta is a lot of things, but most of them are weak to Sicheng and anything he desires. 

“Show me,” he says, pulling off Sicheng’s cock. It’s pointed at the end, pink like the rest of him. Yuta has to admit that he’s wanted it inside him for the longest of times, even before he knew about his tentacles. 

“What?” Sicheng gasps, hands on his back. Yuta has always assumed it to be a Sicheng thing, but it turns out he’s got hands clasped over his folds, keeping his tentacles at bay. Yuta has been _researching_ , admittedly against Sicheng’s instructions. 

He just wants his boyfriend to feel good. 

“I found out,” he whispers into the skin of Sicheng’s stomach. “It’s okay, you can show them to me.” 

“How?” Sicheng pulls back, just a little. Afraid, or so Yuta believes. He keeps trailing kisses up Sicheng’s stomach, up to his sternum, a reassurance. 

“Jaehyun,” he admits, “and I did my research, too.” 

“I asked you not to,” Sicheng frowns. 

“I’m sorry,” Yuta breathes, sucking a dark pink mark into Sicheng’s collarbones. “I just want to make you feel good.” 

“You’re not grossed out,” Sicheng groans as Yuta sinks his teeth into flesh. “I thought humans didn’t like the extras we came with.” 

“This human does,” Yuta pulls away, thumbs over his mark, presses a soft kiss to Sicheng’s lips. “But this human also loves you, all of you, no matter how many dicks you have.” 

“They’re not dicks,” Sicheng pouts. 

“But you can fuck me with them?” 

“I--- sure?” 

“Then I’m not afraid, I’m turned on,” Yuta admits, “you can fuck me while I fuck you, what’s not great about that?” 

“You’re something else,” Sicheng breathes, pressing a kiss against Yuta’s jawline. He allows his hands to fall away, pastel pink tentacles beginning to slither along his sides. 

Admittedly, Yuta’s research has involved porn and a lot of it. Martians fucking humans, mostly, tonguing at the slits on their back as they writhe and moan. Yuta wants to find out if they’re as sensitive as the videos make them out to be, and through his own first-hand experience. 

“Turn over,” he says, his voice dark and husky. He’s had a lot of sex, especially during his time at university. But nothing compares with his time with Sicheng, the flush to his cheeks, the appendages roaming around his chest. 

The first lick along his back folds has Sicheng shuddering, sensitive, overwhelmed. The taste and feeling under his tongue have Yuta reminded of his time with human females back on Earth, but he still has Sicheng’s ass and cock to worship before he moves onto the main event. 

Tentacles, thin and long, follow his tongue as he licks along the opening, curling with it every now and again. Sicheng’s breath hitches as Yuta sucks one, two into his mouth, feeling the texture with his tongue. 

“Feels good,” Sicheng mumbles into the pillow. “Feels _so_ good.”

His tentacles seem more sensitive than their opening, so Yuta redoubles his efforts on them, taking as many into his mouth that can possibly fit. There are so many of them, each one vying for time in the warm heat, minds of their own as they fight over Yuta’s tongue. 

Unoccupied tentacles slip towards Sicheng’s entrance, inserting themselves as he cries out. Their natural lubrication allows for an easy slide, and Yuta has to pull back to enjoy the show. 

“God,” he breathes, watching his boyfriend fuck himself on his own tentacles. “This is the hottest thing I’ve ever seen.” 

“Glad you’re enjoying it,” Sicheng’s breath hitches as Yuta adds his tongue to the mix, licking around his opening. “Cuz I’m having fun.” 

“You want this?” Yuta asks, rubbing a finger over his rim. 

Sicheng responds by flipping himself over onto his back, pulling Yuta down with his hands and tentacles. “Since the moment I saw you,” he admits, pressing a kiss against Yuta’s slick coated lips. 

“I’m not afraid of you,” Yuta kisses him hungrily, groans as one of Sicheng’s tentacles begins to play with his rim, slipping inside. “I want this, too.” 

One tentacle becomes two, three. Sicheng kisses him back with enthusiasm, gasping as his folds slide against the blankets of Yuta’s bed. 

It’s overwhelming, the feeling of Sicheng inside him, the tentacles wriggling as they find their pace, stretching him out and rubbing against his prostate. 

“Can I fuck you?” Yuta breathes, pulls away to pant at Sicheng’s neck. 

“Please,” Sicheng breathes. 

Tentacles, wrapped around Yuta’s cock, help guide him home. Sicheng stills, breathes through his nose, his own cock twitching against his stomach. Legs, arms and tentacles hold him close, those in his ass beginning to thrust as Yuta pushes in. 

“Oh my God,” Yuta can’t help but exclaim. Sicheng is tight, the double sensations of fucking and being fucked has him on edge rather quickly. He won’t last, but judging by Sicheng’s cries, he won’t be far behind. 

He feels something wet and slick at the base of his cock, tentacles wrapping around the length as he pulls out. Slowly, surely, he pushes back in, easing the extra girth into Sicheng, his eyes rolling back at the extra stimulation. 

“Fuck,” he pants, Sicheng’s tentacles jerking his cock while inside himself, the ones in his ass pumping in time with his rhythm. 

Sicheng lies on the bed, shaking limbs wrapped around him, panting into Yuta’s ear as he loses himself to the sensations. He’s so, so pretty like this, tentacles and all, and Yuta can’t help but watch as Sicheng comes undone. 

Hand wrapped around his cock, adding to his pleasure, Yuta loosely jerks him in time with their shared rhythm, until the stimulation has Sicheng coming between them with a groan. 

“Yuta,” he whispers, sleepy and spent, as he tries to find release. 

The tentacle’s in Yuta’s ass thrust lazily, those wrapped around his cock speeding up in contrast. It has him tipping over the edge, orgasm washing over him in waves. 

“You’re beautiful,” Yuta says, collapsing onto Sicheng in exhaustion. They’re sticky with tentacle slick, Yuta’s softening cock still inside of him. But it’s an incredible moment, one he has to treasure. 

He presses kisses to Sicheng’s cheeks, his nose, his lips. Sicheng giggles, plays with Yuta’s hair as he returns them, sleepy and sated. 

“I love you,” he whispers into Yuta’s ear, kisses the lobe as he chases his words. 

The feelings in Yuta’s chest blossom, swell, overwhelm him. 

“I love you too.”

\------

“Nice,” Jaehyun high fives Yuta upon seeing his hickies, the bounce to his step. “I take it things went well?” 

“Amazing,” he says, refusing to give up any further details. “So, tell me about _your_ Martian boy.”

Jaehyun inhales, before going off on a rant about Johnny, the magenta of his skin, the intensity of his kisses. 

Yuta smiles, because he too knows what it’s like to love a Martian. 

Tentacles and all.

**Author's Note:**

> Find more tentacles on [Twitter~](https://twitter.com/pharmarkcy)


End file.
